1. Field of the Invention
The disclosures herein generally relate to a liquid discharge head and an image forming apparatus.
2. Description of the Related Art
Image forming apparatuses such as a printer, a facsimile machine, a copier, a plotter, and a multifunction peripheral (MFP) combining one or more of the above functions include the inkjet recording apparatus, which is a liquid discharge type image forming apparatus that uses a recording head including a liquid discharge head (liquid droplet discharge head) that discharges liquid droplets, for example.
It is noted that liquid discharge defects may occur at the liquid discharge head when foreign matter enters the liquid discharge head and mixes with liquid contained therein. Thus, the liquid discharge head has a filter member arranged in its channel for filtering the liquid.
For example, Japanese Laid-Open Patent Publication No. 2011-025663 (Patent Document 1) discloses a liquid discharge head having a filter member that filters liquid over an entire area of plural liquid chambers in the nozzle array direction, the filter member including a vibrating plate member arranged between a common liquid chamber and a liquid introducing part that is in communication with plural liquid chambers communicating with plural nozzles. The liquid introducing part includes at least a portion facing the filter member that is continuous in the nozzle array direction. The filter member of the disclosed liquid discharge head has plural ribs arranged in the nozzle array direction at intervals of at least two of the liquid chambers.
Also, Japanese Laid-Open Patent Publication No. 2010-018041 (Patent Document 2) discloses a liquid discharge head that has a filter with a lower resistance arranged at a region supplying ink to a liquid chamber in communication with a nozzle that discharges a relatively large amount of liquid droplets compared to the resistance of a filter arranged at a region supplying ink to a liquid chamber in communication with a nozzle that discharges a relatively small amount of liquid droplets.
However, in the above disclosed liquid discharge heads, partition walls for partitioning the liquid chambers are not arranged over the filter member. Also, because the end portions of the partition walls at the filter member side are rectangular, a stagnant region may be formed between the vibration plate member and a channel plate near the partition wall edge portions, and air bubbles may accumulate in this region.